1. Field of the Invention
The present invention relates to a disk drive being used mainly as an auxiliary storage of a computer system for driving such as a magnetic disk, an optical disk, or a magneto-optic disk, and more particularly, to a disk drive having an air filtration system comprising a filter fixed in a casing thereof.
2. Description of Related Art
For an auxiliary storage of computer system, there has generally been used a disk drive to drive such data medium as a magnetic disk, an optical disk, or a magneto-optic disk. In such a disk drive, a disk, as data medium, has been housed in a sealed casing. A recording/reading head which records data on the disk or reads it from the disk floats with a gap of sub-micron order from the surface of the disk by air flow pressure caused by rotation of the disk. Upon rotation, when any dust exists around the head, there is the possibility that the dust entering in between the head and the disk interferes with the stable floating of the head or damages the head and/or the disk itself.
Dust is produced by contact between of the disk and the head, or friction of a bearing of a motor for rotating the disk.
Because of these circumstances, many disk drives are provided with an air filtration system for removing dust having entered therein.
FIG. 1 through FIG. 3 show an embodiment of a conventional disk drive having such an air filtration system.
FIG. 1 is a partially fragmentary plan view illustrating the internal construction of the conventional disk drive.
Reference numeral 1 designates a sealed casing, which is comprised of a base 2 and a cover 3. In addition, the cover 3 is shown to be in its fragmentary state in FIG. 1.
There are fixed to the base 2 a spindle motor (not shown) whose rotary shaft is mounted to a rotahub 4, an actuator 7 for moving a head 6, and a filter 8.
Plural disks 5 are fixed to the rotahub 4 and rotate in the direction of an arrow A.
The head 6 moves promptly to a predetermined position in the radial direction of the disks 5 by the actuator 7.
The filter 8 is fixedly mounted to one corner of the base 2.
FIG. 2 is an enlarged view of the corner of the base 2 in which the filter 8 is mounted.
The filter 8 is fixedly mounted to the corner of the base 2 with fixing screws 9.
FIG. 3 is a perspective view showing an embodiment of the filter 8.
The filter 8 is comprised of a cylindrical holder 10 with quadrilateral sections and a filter member 11 being mounted in the holder 10. The filter member 11 made of fabrics is bent zigzag, and has side peripheries 11c that are glued to the inner surface of the casing 10 so that edges of the bent portions of the filter member 11 can face an opening of the holder 10.
One of the reason why the side peripheries 11c of the filter member 11 are glued to the inner surface of the holder 10 is that any of the side peripheries 11c is cut and frayed to produce waste threads, which is prevented from resulting in dust.
Functional operation of writing/reading of data on the disk 5 by such conventional disk drive as aforementioned is known so well that it is omitted here.
When the disk 5 rotates at high speed in the direction of the arrow A, air flow is generated around it. Part of the air flow shown by an arrow B flows into the opening of the holder 10 of filter 8 and dust being included in the air flow is caught by the filter member 11.
When the filter 8 is assembled, it is necessary to provide a process wherein the side peripheries 11c of the filter member 11 are glued to the inner surface of the holder 10 with adhesive bond. In addition, the fixing screws 9 are needed to fix the filter 8 to the base 2. As has been seen above, assembling the filter 8 and mounting it to the base 2 have required relatively more process steps, which result in a disadvantage of taking more time.